A possible configuration of a computer system for dealing with large-scale data would be a configuration that gathers a plurality of storage apparatuses to be considered as one system. From among possible examples of such a system configuration, there is a possible example in which along with an increase in the number of storage apparatuses, volumes in a certain storage apparatus may be migrated to another storage apparatus for the purpose of load equalization between the storage apparatuses.
Regarding such a computer system, it is desirable that volumes can be migrated without stopping transmission and reception of data between the host computer and the storage apparatuses. If a copy function is applied to migration source volumes at a migration source storage apparatus, it is desirable that the copy function processing should be continued also at a migration destination storage apparatus.
Patent Literature 1 discloses a method for migrating volumes between storage apparatuses without stopping transmission and reception of data between a host computer and storage apparatuses so that the copy function processing executed at a migration source storage apparatus is continued at a migration destination storage apparatus.